Yulia Skripal Is Awake and at the Center of a Russia-U. K. Confrontation

A picture of Yulia Skripal obtained from her Facebook account. A month after being poisoned by a rare nerve agent, she is awake and talking.CreditCreditYulia Skripal

LONDON — Russian television broadcast a telephone recording on Thursday said to be of Yulia Skripal, who was poisoned with a military-grade nerve agent a month ago and is at the center of an escalating confrontation between Russia and Britain.

In the recording, which the Rossiya 24 news announcer emphasized could not be verified, Ms. Skripal tells her cousin Viktoria that both she and her father, Sergei V. Skripal, are healthy, and that neither of them has suffered long-term health damage from the poisoning. The recording contradicted public statements by the British authorities, who have described Mr. Skripal’s condition as “critical but stable” and said that only Ms. Skripal was conscious.

Within hours of the program’s broadcast, the British police released a statement on Ms. Skripal’s behalf, in which she said that she “woke up over a week ago now” and that her “strength is growing daily.”

The authorities have released little information about the attack on Mr. Skripal and his daughter, but they have expressed certainty that it was carried out on behalf of the Russian government. Officials have said Mr. Skripal, a former Russian spy turned double agent who was living peacefully in southwestern England, was very likely targeted as an example to future defectors. Moscow has denied the accusations and has seized on the ambiguities surrounding the investigation in an aggressive campaign to discredit the British authorities.

At the United Nations on Thursday, the Russian ambassador, Vasily A. Nebenzya, called an emergency session of the Security Council where he accused the British authorities of everything from planting false stories in the media to neglecting Mr. Skripal’s pet cats and guinea pigs. He gave an impromptu lecture about Dostoyevsky’s “Crime and Punishment” and quoted at length from “Alice in Wonderland.”

“This is some kind of theater of the absurd,” he said. “What, you were unable to find a more believable fake?”

Britain’s public case against Russia has so far rested largely on the nerve agent, an unusual chemical weapon developed in the last years of the Soviet Union. But this week, the chief executive of the Defense Science and Technology Laboratory at Porton Down, Britain’s premier chemical weapons laboratory, said its scientists could not identify “the precise source” of the chemical, though it was almost certainly created by a “state actor.”

That conclusion undercut statements by Foreign Secretary Boris Johnson that Porton Down scientists had “categorically” traced the agent to Russia. Mr. Johnson swiftly came under criticism from Jeremy Corbyn, the leader of the opposition Labour Party, who said the foreign secretary had “exceeded the information he had been given” and had “egg on his face.”

Diane Abbott, another Labour leader, took aim at Mr. Johnson in an interview with the BBC, saying, “so many people were willing to rush to the media and say it was unequivocally Putin.”

“We will, I hope, get some credit for taking a more thoughtful approach and asking the right questions,” she said.

At the Security Council, Britain’s closest allies reiterated their support for the conclusion that Russia was behind the poisoning.

“We share the U.K.’s assessment, namely that there is no other plausible explanation other than Russia’s responsibility,” said France’s ambassador, François Delattre. His sentiments were echoed by the representatives from the United States, Sweden, the Netherlands and others.

In her remarks to the Security Council, Britain’s ambassador, Karen Pierce, responded calmly to the barrage of Russian accusations, providing what she described as “intellectual clarity.”

About 250 police detectives are involved in the investigation, she said. They are reviewing 5,000 hours of surveillance video, examining 1,300 exhibits and interviewing 500 witnesses. “The U.K. has launched one of the most comprehensive and complex investigations into the use of a chemical weapon ever,” Ms. Pierce said.

She also brought some of her own literary references. Responding to Mr. Nebenzya, who a few weeks ago compared British investigators on the case to the hapless Inspector Lestrade from the Sherlock Holmes stories, Ms. Pierce compared Russia to Holmes’s nemesis, Professor Moriarty.

A new challenge could come within a few days if Viktoria Skripal, Mr. Skripal’s niece, follows through on plans to travel to Britain. Alexander Yakovenko, the Russian ambassador in London, said at a news conference on Thursday that he had offered Ms. Skripal assistance with transport, accommodation and Russian-English translation during her visit.

Viktoria Skripal has repeatedly expressed doubts about the British accusations, suggesting that her relatives could have been sickened by bad fish or attacked by the mother of Yulia Skripal’s boyfriend. She has made several appearances on Russia’s state-controlled television in recent days, in one case appearing alongside the two men accused of having poisoned Alexander Litvinenko, another former Russian spy, in London in 2006.

In the conversation broadcast Thursday on Russian television, Yulia Skripal tells her cousin that she will probably not get a British visa and they probably would be unable to see each other.

Michael Schwirtz contributed reporting from the United Nations.

A version of this article appears in print on , on Page A10 of the New York edition with the headline: Poison Victims’ Health Improves. British-Russian Tone Worsens.. Order Reprints | Today’s Paper | Subscribe